Simple Method For Determination Research Articles

A simple, easy, and efficient HPTLC method for simultaneous determination of polyamines (putrescine, spermidine, and spermine) in plant tissues

Polyamine analysis has received a lot of attention in recent years because they are important in several physiological processes, including cell proliferation, differentiation, and growth. This study presents the development and validation of a user-friendly and convenient high-performance thin-layer chromatography (HPTLC) method, using benzoyl chloride as a derivatization agent for the analysis of three abundant polyamines. A comparative study with HPLC-MS/MS was performed to evaluate the putrescine, spermidine, and spermine content of plant tissues. The linear ranges for the determination of putrescine and spermine by HPTLC were lower than those of HPLC-MS/MS. Lower LODs were found for polyamine analysis using HPLC-MS/MS except for spermidine. The Pearson correlation coefficients of the two methods for putrescine, spermidine, and spermine were 0.982, 0.998, and 0.980, respectively, which confirms the applicability of both HPTLC-UV and LC-MS/MS methods. According to these results, the optimized HPTLC-UV method may be used as a practical analytical tool for screening polyamine levels in the horticultural, food, and pharmaceutical industries for quality control purposes.

A novel device for the determination of liposome/water partition coefficients

A novel, cheap and easy-to-construct device and a simple method for partition coefficient determination in liposome/water system based on modified equilibrium dialysis have been developed. The device consists of two vials separated by a semi-permeable membrane, through which the free form of a low molecular weight substance is transported by shaking assisted diffusion. Five test substances, eugenol, carvacrol, thymol, 4-hydroxybenzyl alcohol (4-HBA) and butylparaben were analyzed after equilibration in aqueous phase by three methods, HPLC-UV, GC-MS and DPV with comparable results. This shows the possibility of using the proposed method in any laboratory with any equipment capable of analyzing the substance under study. The liposome/water partition coefficients (log Pl/w) determined for eugenol (2.39), thymol (2.83), carvacrol (2.78) and butylparaben (3.30) are consistent with previously published data. A strong effect of NaCl on the liposome/water partition coefficient was observed. The value of log Pl/w = 1.06 determined for 4-HBA in the presence of 0.15 mol L-1 NaCl in the partitioning liposomal system was considerably lower than in the absence of the salt (log Pl/w = 2.06). The developed method was used to determine the partition coefficient of morphine in liposome/water system without NaCl (log Pl/w = 2.65) under given conditions.

Optimization and Validation of Sensitive UPLC-PDA Method for Simultaneous Determination of Thymoquinone and Glibenclamide in SNEDDs Formulations Using Response Surface Methodology

The development of analytical procedures capable of simultaneous determination of two or more drugs is in crucial demand due to the availability of different formulations that are composed of different APIs. The presented study aimed to optimize and validate a simple, accurate, and sensitive UPLC analytical method for the simultaneous determination of thymoquinone (TQ) and Glibenclamide (GB) using response surface methodology, and apply this method in pharmaceutical formulations. A 32 full design of experiment was utilized to study the impacts of the independent parameters (acetonitrile ACN concentration, A; and column temperature, B) on the drugs’ analytical attributes (viz, retention time, peak area, and peak asymmetry, in addition to the resolution between TQ and GB peaks). The results revealed that the independent parameters exhibited highly significant (p < 0.05) antagonistic effects on retention times for TQ and GB peaks, in addition to the agnostic effect on GB peak symmetry (p-value = 0.001). Moreover, antagonistic impacts (p < 0.05) on the resolution between TQ and GB peaks were found for both independent factors (A and B). The statistical software suggested 46.86% of ACN (A) and 38.80 °C for column temperature (B) for optimum analytical responses. The optimized green method was discovered to be acceptable in terms of selectivity, precision, accuracy, robustness, sensitivity, and specificity. Moreover, the optimized simultaneous method was successfully able to determine the contents of TQ and GB in self-nanoemulsifying drug delivery (SNEDD) formulation, in which the results showed that GB and TQ content within the prepared formulations were 1.54 ± 0.023 and 3.62 ± 0.031 mg/gm, respectively. In conclusion, the developed assay was efficient and valid in analyzing TQ and GB simultaneously in bulk and self-nanoemulsifying drug delivery system (SNEDDs) formulations.

Establishment of iterative modeling method for spherical tensegrity structure using rotational symmetry and regular polyhedron configuration

Tensegrity structures are attractive light-weight structures. In particular, spherical tensegrity structures are expected to be applied in various fields. This article proposes a simple method for modeling spherical tensegrities. Firstly, the nodal coordinates of the spherical tensegrity are systematically determined based on rotational symmetry and regular polyhedral configuration. This approach enables the systematic acquisition of the nodal coordinates of spherical tensegrities of all sizes by introducing a three-dimensional rotation matrix and the dihedral angle of the regular polyhedron. Secondly, the prestress ratio is determined iteratively. For the stability analysis of the spherical tensegrity, nonlinear analysis with prestress is required. For the analysis considering the prestress, a tangent stiffness matrix is applied in this study. The simple determination method enables the modeling of spherical tensegrities. The natural frequencies and mode shapes of the spherical tensegrity are identified by frequency analysis. A vibration experiment is conducted as a verification experiment. The natural frequencies from the analysis are compared to the resonance frequencies from the experiment. This comparison confirms the validity of the frequency analysis results, based on the two proposed methods.

Validation of a simple spectrophotometric method for the rapid determination of salicylates in plasma

IntroductionThe determination of salicylate concentrations constitutes a critical aspect of medical diagnostics, particularly in emergency settings. High-performance liquid chromatography (HPLC) and spectrophotometry are efficient methods commonly utilized for this purpose. In emergency laboratories with limited resources, the validation of a cost-effective and reliable spectrophotometric method for salicylates in plasma becomes imperative. The present study aims to validate such a method, ensuring its applicability in toxicological emergencies within resource-constrained laboratories. Materials and methodsThe proposed spectrophotometric analysis relies on detecting salicylic ions amidst the presence of ferric salts, resulting in the formation of a distinct purple chelate complex. To ascertain the method's credibility, the validation guidelines established by the European Medicines Agency (EMA) were employed as a benchmark. A comprehensive validation process was conducted over a three-day period, with three levels of validation standards being considered. ResultsFollowing the EMA protocol, the spectrophotometric method demonstrated commendable fidelity, accuracy, and linearity over a concentration range of 50 to 500 mg/L. The limit of detection and quantification was found to be 10 and 50 mg/L, respectively, and the correlation coefficient was determined to be R2 = 0.998. However, it is essential to acknowledge that interference with phenothiazines occurred at concentrations ranging from 50 to 100 mg/L. Despite this, the method's average sensitivity remains viable for practical use in cases of poisoning. The accuracy per concentration level proved satisfactory, with relative biases remaining below 15%, and the confidence intervals of mean recovery closely approximating the desired target value of 100%. ConclusionIn conclusion, the presented spectrophotometric method stands out as an economical, straightforward, and user-friendly approach, ideally suited for toxicological emergencies when resources are limited. The method delivers satisfying results, establishing its practical utility in critical medical scenarios. This validated method holds immense promise for emergency laboratories facing resource constraints.

Simple andrapid detection ofthree amatoxins andthree phallotoxins inhuman body fluids by UPLC-MS-MS andits application in15 poisoning cases.

Amatoxins and phallotoxins are toxic cyclopeptides found in the genus Amanita and are among the predominant causes of foodborne sickness and poisoning-related fatalities in China. This study introduces and validates a simple, rapid and cost-effective ultra-performance liquid chromatography-mass spectrometry method for the simultaneous determination and quantification of α-amanitin, β-amanitin, γ-amanitin, phallisacin, phallacidin and phalloidin in human blood and urine. Quick therapeutic decision-making is supported by a 9 min chromatographic separation performed on a Waters Acquity UPLC HSS T3 column (100 mm × 2.1 mm, 1.8 µm) using a gradient of high-performance liquid chromatography (HPLC)-grade water and methanol:0.005% formic acid. The analyte limit of quantification was 1-3 ng/mL in blood and 0.5-2 ng/mL in urine. Calibrations curves, prepared by spiking drug-free blood and urine, demonstrated acceptable linearity with mean correlation coefficients (r) greater than 0.99 for all phallotoxins and amatoxins. Acceptable intraday and interday precision (relative standard deviation <15%) and accuracy (bias, -4.8% to 13.0% for blood and-9.0% to 14.7% for urine) were achieved. The validated method was successfully applied to analyze 9 blood samples and 2 urine samples testing positive for amatoxins and/or phallotoxins. Amatoxins and/or phallotoxins were identified in each whole blood sample at a range of 1.12-5.63 ng/mL and in two urine samples from 1.01-9.27 ng/mL. The method has the benefits of simple sample preparation (protein precipitation) and wide analyte coverage, making it suitable for emergency quantitative surveillance toxicological analysis in clinics and forensic poisoning practice.

A solvent-free HPLC method for the simultaneous determination of Favipiravir and its hydrolytic degradation product

During COVID-19 pandemic, Favipiravir (FPV) showed a great efficacy against COVID-19 virus, it produced noticeable improvements in recovery of the patients. The aim of this study was to develop a new, green and simple method for the simultaneous determination of FPV and its acid-induced degradation product (ADP) in its pure and pharmaceutical dosage forms. This method will be key for the inevitable development of FPV solution and inhaler formulations. A green micellar RP-HPLC method was developed using an RP-VDSPHERE PUR 100 column (5 µm, 250 × 4.6 mm) and an isocratic mixed micellar mobile phase composed of 0.02 M Brij-35, 0.1 M SDS and 0.01 M potassium dihydrogen orthophosphate anhydrous and adjusted to pH 3.0 with 1.0 mL min−1 flow rate. The detection was performed at 280 nm with a run time of less than six min. Under the optimized chromatographic conditions, linear relationship has been established between peak area and concentration of FPV and its ADP in the range of 5–100 and 10–100 µg mL−1 with elution time of 3.8 and 5.7 min, respectively. The developed method was validated according to the ICH guidelines and applied successfully for determination of FPV in its pharmaceutical dosage form.

Validated HPLC method for simultaneous quantitative determination of dimethylcurcumin and resveratrol in pluronic-F127 nanomicelles: Formulation with enhanced anticancer efficacy

Nano-micelles offer a promising vehicle for the delivery various therapeutically significant biologicals. Development of convenient and efficient chromatographic methods for the quantitative determination of the active pharmaceutical ingredients in such systems is of immense importance. In this study pluronic-F-127 nano-micelles were prepared and loaded with dimethylcurcumin (DMC) and resveratrol (Res). A simple, convenient and effective HPLC method was developed for the quantitative estimation of DMC and Res in the polymeric nano-micelles through a single injection. A reverse-phase ACE® C18 column (250 mm × 4.6 mm) was used with a gradient mobile phase system consisting of 1 % MeOH and 0.1 % H3PO4:100 % acetonitrile at 1 mL/min flow rate with UV detection for Res, and fluorescence detector for DMC. The calibration curves generated for both the compounds were found linear with r2 values of 1.000 over a concentration range of 2–25 µg/mL with low limit of detection (LOD) values of 0.37 and 0.16 µg/mL for DMC and Res respectively and limit of quantification (LOQ) values of 1.23 and 0.55 µg/mL for DMC and Res respectively. Similarly, accuracy was found in a range of 98.80 -102.47 % for DMC and 100.58–101.77 % for Res. Furthermore, the within-run precisions (%RSD) were 0.073 - 0.444% for DMC and 0.159 - 0.917% for Res, while between-run precisions (%RSD) were 0.344 - 1.47 for DMC and 0.458 - 1.651 for Res. Moreover, the DMC with Res co-loaded nanomicelles showed higher activity against MCF-7 and MDA-MB 231 compared to DMC and Res alone. Overall, this study presented a simple, convenient, precise and accurate method for the quantitative determination of DMC and Res in polymeric nano-micelles which have anticancer potential.•A simple HPLC for the quantitative determination of DMC and Res in nanomicelles having anti-cancer potential.•Non complicate with high degree of recoveries of sample preparation process.•This method can be used to determine a mixture of DMC and Res in pharmaceutical formulation in single injection.

A simple and rapid external standard calibration HPLC method for determination of lumefantrine in dried blood spot samples from malaria patients in Botswana.

A simple external calibration liquid chromatography-diode array detector method was developed, validated, and applied for the determination of lumefantrine (Lum) in dried blood spot (DBS) samples collected from malaria patients in Botswana. The samples were validated in accordance with the United States Food and Drug Administration guidelines for bioanalytical methods after sample preparation using solid-liquid extraction. Separation was achieved using an XTerra C18 column (50 × 4.6mm,5μm), and a binary solvent system of acetonitrile and water adjusted to pH2.3 was used as the mobile phase. The validated method was applied for the determination of Lum in DBS samples collected from malaria patients infected with Plasmodium falciparum in Botswana. The calibration curve was linear between 0.5 and 12 μg/mL with a coefficient of determination (R2 ) of 0.9996. The limit of detection and the lower limit of quantification were 0.5 and 1.4μg/mL, respectively. The efficiency of extraction measured as percentage recovery ranged between 84.2% and 107.8% at the three quality control (QC) levels, that is, low QC, mid QC, and high QC. In conclusion, data suggest that the method is suitable for the determination of trace Lum in biofluids and can also be used for therapeutic drug monitoring and pharmacokinetic profiling.

A Titration Method for Standardization of Aqueous Sodium Chlorite Solutions Using Thiourea Dioxide.

Accurate and cost-effective methods for the analysis of oxychlorine compounds in water are critical to modern chlorine-based water treatment. With alternatives to elemental chlorine and hypochlorite bleaches growing in popularity, simple quantification methods for the disinfectant chlorine dioxide (ClO2) in water, as well as chlorite (ClO2-) and chlorate (ClO3-), which are commonly used precursors in ClO2 generation, are required. However, currently, regulated standard methods require specialized equipment and do not effectively discriminate between molecular and ionic species. In this contribution, we present a simple titration-based method for chlorite determination in water using commercially available and easy-to-handle reagents. Specifically, chlorite is reduced with a slight excess of thioureadioxide (TUD). The remaining reductant is then back-titrated against a known amount of potassium permanganate, affording calculatable chlorite concentrations through measured consumption of a reductant and a clear visual endpoint upon accumulation of excess KMnO4. Straightforward methods for chlorite standardization with reasonable error and accuracy for field and/or lab application have the potential to greatly enhance quality assurance and therefore assist in resource deployment in water treatment.

Solid-phase Spectrophotometric Determination of Synthetic Food Colourants in Confectionery Products

Abstract: We suggest a simple method of solid-phase spectrophotometric determination of the following synthetic food colourants: quinoline yellow Е104, sunset yellow FCF Е110, Ponceau 4R Е124, patent blue V Е131, brilliant blue FCF Е133. Methods: The method implies the use of a polymethacrylate matrix for solid-phase extraction of these colourants from confectionery products. Results: While the contact time for the matrix and the colourant solution was 15 minutes, the detection limits were 1.7; 1.6; 5.8; 2.9; 2.9 mg·L–1 for colourants E104, E110, E124, E131, E133, correspondingly. The standard deviation of the results by determination of synthetic food colourants in confectionery products did not exceed 13 %. Conclusion: Compared to spectrophotometric determination involving liquid solvent extraction, the method of determination of synthetic colourants we developed offers the following advantages: sufficient increase of determination sensitivity, which results from accumulation of the analyte and elimination of the possible aliquote turbidity as well as zero colourant loss by absorption into supernatant liquid and the solid phase of the matrix.

A study on the applicability of one-step vortex extraction and purification combined with gas chromatography-tandem mass spectrometry for analysis of four skin penetration enhancers in cosmetics

Based on one-step vortex extraction and purification combined with gas chromatography-tandem mass spectrometry (GC–MS/MS), we established a simple, rapid, and efficient method for the simultaneous determination of four skin penetration enhancers in cosmetics, including isosorbide dimethyl ether, isopropyl myristate, N-butylsaccharin and Azone. The extraction procedure was performed in a centrifuge tube, allowing extraction and purification in a single step. The cosmetic sample was extracted by n-hexane-ethyl acetate (1:1, V/V), purified by silica gel and anhydrous magnesium sulfate as the solid phase purification agent, separated on a TG-5 ms column (30.0 m × 0.25 mm × 0.25 μ m), confirmed and detected by GC–MS/MS in the selected reaction monitoring (SRM) mode, and quantified by the internal standard method with Di-n‑butyl phthalate-D4(DBP-D4) as the internal standard. The selections of a column, extraction solvent, and solid phase purification agent were optimized. Under the optimized conditions, the four skin penetration enhancers showed good linearities in the range of 0.02∼0.50 mg L − 1. The correlation coefficients (r) were 0.992 ∼ 0.997, exceeding the specifications requirements (r ≥ 0.990); The detection (LODs, S/N = 3) and quantification limits (LOQs, S/N = 10) of the method were 0.08 ∼ 0.12 mg kg−1 and 0.25 ∼ 0.40 mg kg−1, respectively. According to the cosmetic matrix in different formulation systems, the spiked recovery tests were carried out at three levels, i.e., low, medium, and high. The average recoveries of the analytes were 85.3% ∼ 95.6%, and the relative standard deviations (RSDs, n = 6) were 2.1% ∼ 7.8%. The established method was also employed to analyze cosmetics in the market. Azone, isosorbide dimethyl ether, and isopropyl myristate resulted as the most widely used skin penetration enhancers in cosmetics. The method established in this study has the advantages of operational simplicity, high sensitivity, good reproducibility, and low consumption of samples and solvents. Moreover, it can be used to determine skin penetration enhancers in cosmetics.

A simplified method for determination of the optimal feed temperature for hydrogen peroxide decomposition process occurring in an immobilized enzyme packed-bed reactor

A simplified method for determination of the optimal feed temperature for hydrogen peroxide decomposition process occurring in an immobilized enzyme packed-bed reactor

BaTiO3 is a novel adsorbent for solid-phase extraction of copper at trace levels in food and water samples before HR-CS-FAAS detection

A simple, precise, and rapid method for preconcentration and determination of copper in food and water samples, based on sonication/vortex-free solid phase extraction with high resolution-continuum source flame atomic absorption spectrometry has been developed. In this study, BaTiO3 was synthesized using a single-step hydrothermal method and used as an adsorbent. BaTiO3 was characterized by FT-IR, SEM-EDX, STEM, XRD, and BET methods. The significant feature of the adsorbent is its high surface-to-volume ratio (177.4 m²/g). Important parameters (pH, adsorbent amount, eluent type and volume, adsorption and desorption time, model solution volume, and matrix effects) were optimized. The linear working range (5 – 250 µg L-1) and the detection limit (1.6 µg L-1) were calculated. The presented method was validated with certified reference material and the addition-recovery tests. The application of the method was evaluated for the extraction and determination of Cu(II) in selected food and water samples and quantitative data were obtained.

Fast, simple HPLC method for determination of Spironolactone related compounds

Fast, simple HPLC method for determination of Spironolactone related compounds

Spectrophotometric method development and validation for determination of pazopanib in the bulk and the formulation

The present work is performed on analytical method development with its latter validation study of a simple and accurate UV-Visible spectrophotometric method for the content determination of the Pazopanib HCl (PAZ). The optimum conditions and solvent selection for the analysis of the drug were established. Absorption maxima (λmax) taken for the analysis was 267nm in the purposed medium. Calibration curve was obtained and plotted against the observed values. Validation of the method was performed as per the current ICH guidelines for linearity, accuracy, precision, LOD and LOQ. The method is simple, accurate, sensitive, precise and reproducible. The method can be used in IPQC and QC testing on a commercial stage as well as in small scale labs, as the method is economical and cheap. The analysis is done on UV-Visible spectrophotometer which is easily available in every institute or in small labs as well.

Furosemide Determination in Pharmaceutical Samples Using Differential Pulse Polarographic method

The research includes the development of a simple, sensitive and accurate differential pulse polarography method for the quantitative determination of furosemide drugs in pharmaceutical preparations and in their pure and commercial forms, the electrochemical behavior using the dropping mercury electrode DME, as well as finding the values of the half-wave potential (E1/2) as a qualitative value, the number of electrons that were transferred and participating in the reduction process. The furosemide drug showed a clear reduction peak at a voltage of (-0.24) volts under optimal conditions. The correlation coefficient for furosemide at a concentration range of (2–24) µg.ml-1 was 0.9969, the LOD and LOQ of the drug were 2.139 and 7.129, respectively, and the average relative standard deviation (RSD) of the drug was 1.41%, with recovery of the f drug 97.58% and (n =5).

Development of sugars quantification method using polarimeter couple with UV-Visible quartz cuvette cell

The objective of this study was to develop the method for determination of sugars at low sample volume using UV-Visible quartz cuvette cuvett instead of polarimeter cell. This proposed method could be analysis of sugars with high sample throughput rate and appropriate for analysis of pharmaceutical formulation. This study, the simple determination method by using sample UV-Visible quartz cuvette was developed in order to analyze dextrose, sucrose and lactose. It was found that quartz cuvette was not affected from the sodium light source at wavelength of 589.0 nm and it was possible to adapt for polarimetry technique. The linear calibration curve of dextrose, sucrose and lactose standard solution using polarimeter sample tube were constructed in the concentration ranges of 2.5–15.0 % w/v. Linear regression between the angle of rotation (y) and concentration of each sample (x) were expressed as the equation of y = 1.0941x – 0.1824 (r2= 0.9993), y = 1.3515x –0.1581 (r2= 0.9998) and y= 1.0390x – 0.0162 (r2= 0.9997) for dextrose, sucrose and lactose, respectively. Interestingly, the calibration curve of sugars standard solution using UV-Visible quartz cuvette were shown as y = 0.1050x - 0.1038 (r2= 0.9990), y = 0.1312x – 0.1458 (r2= 0.9989) and y = 0.1072x – 0.0335 (r2= 0.9991) for dextrose, sucrose and lactose, respectively. The detection limits (LOD) of proposed method for determination of dextrose, sucrose and lactose were 0.5, 1.0 and 0.6 % w/v, respectively, while the quantitation limits (LOQ) were 1.6, 3.0 and 1.9 %w/v for anlysis of dextrose, sucrose and lactose, respectively. The interferences study for proposed method from sodium chloride was investigated. It had found that this salt shown none effect for the proposed method. The results acquired the proposed method were compared favorably with those acquired by the reference method at a 95% confidence level with no significant difference (n=10). The developed method had shown accurate, precise, and reproducible. Moreover, this method indicated the possibility of a modified polarimetric method for the quantification of sugars. The method is possible to apply both in simple quality control laboratory and local industrial that involved with pharmaceutical production.

Highly sensitive and simple fluorescence-based method for trace level residue determination of pinoxaden in agricultural and environmental samples: Experimental and DFT study

Keeping in view the toxicity of pesticides, development of analytical methods for their determination in environmental samples is the need of the day. Herein, a simple, fast and sensitive method for the determination of pinoxaden has been described. The kinetically stable, Fe(III) based complex of pinoxaden was formed at room temperature showing maximum fluorescence intensity at 337 nm with 0.2 µg mL−1 of Fe(III) at pH 9. The complex shows a linear response in the concentration range of 1 × 10−4-1 × 10−3 µg mL−1 with a coefficient of determination R2 = 0.9917, limit of detection and limit of quantification of 8.1 × 10−5 and 2.4 × 10−4 µg mL−1, respectively, and relative standard deviation and maximum matrix effect of 0.021% and 2.13%. Density functional theory simulations were used to understand the nature of Fe(III) based complex of pinoxaden. The larger negative interaction energy of −1.11 eV evince that the Fe(III) strongly coordinated with the N-atom shared by oxadiazopine ring and the pyrazole ring and the O atom of –CO group of side chain, which are consistent with the experimental results. Interference study shows that among the metal ions studied, only Cu(II), Co(II) and Pb(II) show reasonable interference effect. The proposed approach was applied to quantify pinoxaden in the formulation and real agricultural and environmental samples. The results indicate excellent recovery in the range of 89.44 ± 1.38–97.51 ± 2.62 % for wheat, barley, water and soil samples. In soil samples no residue was quantified while in the wheat and barley samples the residue found was below the maximum residue limit. Under optimized experimental conditions, the proposed method was found to be simple, fast, reasonably interference free and has trace level sensitivity. The method was found to be comparable and even superior to some literature methods for determination of pinoxaden in complex matrices.

A simplified D3 -creatine dilution method for skeletal muscle mass determination with dynamic correction of creatinine and D3 -creatinine using ultra-performance liquid chromatography-tandem mass spectrometry.

This study developed a simple method for muscle mass determination based on D3 -creatine dilution by removing the matrix effects of ultra-performance liquid chromatography-tandem mass spectrometry analysis through mutual correction of creatinine and D3 -creatinine. Rats were administered an oral tracer dose of D3 -creatine at age 6weeks. Creatinine and D3 -creatinine in urine were detected using ultra-performance liquid chromatography-tandem mass spectrometry after diluting 20 times to obtain D3 -creatinine enrichment factor (mole percent excess). The mole percent excess obtained from peak area could be used to calculate muscle mass using the improved formula. The limit of detection was 0.500 ng/mL for D3 -creatinine. Creatinine and D3 -creatinine could be mutually corrected because of the same matrix effect, and D3 -creatine spillage was negligible within 0.22%. Isotopic steady time was consistent with that obtained using conventional methods. Bland-Altman plots demonstrated the satisfying consistency between the proposed method and magnetic resonance imaging. This is a simple and rapid measuring method of muscle mass based on D3 -creatine dilution that requires no accurate quantification of creatinine and D3 -creatinine concentrations and no urine sample collection to obtain D3 -creatine spillage.